Preparation of titanium dioxide concentrates and iron oxide pigments from ilmenite
Abstract
Abstract ILMENITE, PREFERABLY AFTER PRE-OXIDATION, IS REDUCED TO CONVERT IRON OXIDE CONTAINED THEREIN TO IRON, THE ILLMENITE IS TREATED WITH NITROBENZENE AT ABOUT 20 TO 100*C. AND A PH OF 3 TO 7 OXIDIZE THE IRON TO IRON OXIDE PIGMENT WHICH CAN BE SEPRATED IN RELATIVELY PURE FORM FROM THE TITANIUM DIOXIDE CONCENTRATE. THE CONCENTRATE IS THEN PREFERABLY LEACHED WITH ACID TO REMOVE RESIDUAL IRON IMPURITIES AND LEAVE A RELATIVELY PURE TITANIUM DIOXIDE SUITED FOR CHLORINATION. MODIFYING AGENTS PRESENT DURING THE NITROBENZENE OXIDATION WILL AFFECT THE COLOR OF THE IRON OXIDE PIGMENT. TO FACILITATE CLEAN SEPARATION OF THE IRON OXIDE PIGMENT FROM THE TITANIUM DIOXIDE CONCENTRATE THE REDUCED ILMENITE SHOULD NOT CONTAIN AN APPRECIABLE AMOUNT OF PARTICLES WITH GRAIN SIZES OF LESS THAN ABOUT 40 MICRONS.
Inventors
- 👤 H Bade
- 👤 A Bellefontaine
- 👤 G Kienast
Bibliographic Details
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